Electrical apparatus



May 3L 192?o 1,631,085

T. w. CASE ELECTRI CAL APPARATUS Filed Avril 16, 1923 Patented May 31,1927.

flHEOIDORE WILLARD CASE, OF AUBURN, NEW YORK.

ELECTRICAL APPARATUS.

Application filed April 16, 1923. Serial No. 632,496.

This invention relates to a new and improved electrical apparatus,particularly adapted for translating sound waves into light waves orvariations of light waves which can be efficiently photographed orreproduced upon a film, thereby constitutlng a translatable film recordof sound waves, particularly articulate or musical sound waves. 7

I have produced and my invention includes as a separable element, aninstantane nus varying light source of a most efiicient character,highly actiuic for photographic purposes and operable with comparativelylow voltage, and peculiarly adapted for the production of a clear,distinct and read ly translatable photograph of electrical variaations,especially as effected by variatlons in sound Waves.

Other objects and advantages relate to the details of the apparatus, allas will more fully appear from the following description, taken inconnection with the accompanying drawings, in which Figure 1 is adiagrammatic illustration of an embodiment of my invention.

Figure 2 is a diagrammatic illustration of another embodiment of myinvention.

Figure 3 illustrates a somewhat different form of hook-up.

The apparatus as shown comprises a microphone 1- connected in circuitwith a source of potential, as battery 2 and the primary ,-3 ofatransformer 4,

the secondary 5 of which is connected in circuit with the filament 6-and grid -7- of an electron-discharge device :8-, the plate '9 of whichis connected in circuit with a source of potential, as battery -10--,the primary 11 of a transformer -12- and the filament 6- of theelectron-discharge device.

The filament --6 may be heated in any suitable manner, as by connectionin circuit with the source of potential, as battery -9A. The secondary-13 of the transformer -12 is preferably connected in circuit with asource of potential, as battery 17 and the two spaced electrodes 14- and15 disposed within the bulb 16- which may, perhaps, preferably be formedof glass with a quartz end through which the rays pass to thephotographing apparatus. The electrodes may be of any desired form andas here illustrated, the electrode l4.- 1 s 1n the form of acomparatively small cylmder which may perhaps preferably be formed of amaterialsuch as aluminum to reduce the cathode sputtering and consequentdarkening of the glass or quartz endplece of the bulb 16.

Preferably the electrodes are arranged in close proximity, as forinstance, a distance of about th to %th of an inch, altho wide variationmay be had in that respect.

The essential feature of this invention re- SKlGS particularly in themeans provided for effecting operation of this bulb with comparativelylow voltage, and further in the production of a variable light highlyactinic for photographic purposes, and this is effected in accordancewith the invention here disclosed by coating one or both of theelectrodes with a rare earth oxide, such as thorium, cerium, etc, whichmaterials in the combination here disclosed accomplish the object ofthis invention.

My present experience leads me to believe that the advantages of thisinvention are attained by reason of the fact that the coating materialconsisting of or comprising a rare earth oxide as described, gives offelectrons at room temperature under an impressed voltage whereby theoperation of the lamp can be effected with comparatively low voltage inthe production of a light highly actinic for' photographic purposes, andthe lamp is capable of carrying a much greater current when once inoperation as compared with a lamp in which such a coating is notpresent. Also the character of the light is etter.

The bulb 16 should contain an easily ionizable gas, such as preferablyhelium, altho argon or other gases may be used, and by the expression aneasily ionizable gas, as used in the specification and claims hereof, Ido not mean to limit myself to one particular character of gas, butrather use the expression as illustrative of any easily ionizable gas,whether it be of a single kind or character, or a combination or mixtureof gases, as for instance, helium and argon.

The light produced by the lamp of this invention is highly concentrated,and may, if desired, be made of very small size particularly desirablefor photographic purposes when a lens -19- is used for focusing thelightv upon a film -l8 moving past the relatively small orifice 23- inthe usual manner of photographin As before stated, the electrode 14-- ishere shown in the form of a small cylinder, as for instance was of aninch in diameter, and preferably the interior only of the cylinder iscoated with a rare earth oxide or oxides. The electrode 15 may perhapspreferably, as shown, terminate near the base of the cylinder or may, ifdesired extend some distance into the cylinder.

In F igure 2 a structure is shown substantially similar to thatillustrated in Figure 1, except that the electrode 15 is Shown in theform of a filament so that if desired,

the same may be heated in any usual manner, as by a source of potential(not shown) or may be used as an unheated electrode in former -12 isomitted and the electrodes -1-'1 and -15- are connected directly incircuit with the plate 9- and filament -6 of the electron-dischargedevice -8.

As heretofore stated, it is In present opinion that the advantages ofhis invention are attained by reason of the fact that one or both of theelectrodes is coated with a rare earth oxide that gives off electronsunder an impressed voltage, but the operation of this coating may be ofsome other character and may not be due entirely or at all to theemission of electrons, and for that reason I do not desire to statepositively the exact method of operation of the lamp, but limit mypositive description to the fact that advanta' es are attained by theapparatus as described without regard to the particular reasonstherefor, and I do not desire to limit myself to the form, shape orarrangement of the electrodes or any particular method of applying thecoating of rare earth oxide or oxides, as various changes may be madeWithout departing from the invention as setforth in the appended claims.

I claim 1. In an apparatus for producing a photographic record of lightvariations corresponding to electrical variations, a bulb containing apair of electrodes spaced apart a distance not greater than one inch,and the negative one of said electrodes comprising a rare earth oxide,and a gas within the bulb at such a pressure that an intenseconcentrated glow is produced about the negative electrode.

2. In an apparatus for producing a photographic record of light wavevariations corresponding to electrical variations, a bulb containing apair of unheated electrodes in an atmosphere of an inert gas at. such apressure that a glow is concentrated about the negative electrode atoperating voltage, and the negative one of said electrodes comprising arare earth oxide.

3. In an apparatus for producing a photographic record of light wavevariations corresponding to electrical variations, a bulb containing apair of unheated electrodes in an atmosphere of helium at. such apressure that a glow is conotmtrated about the negative electrode atoperating voltage, and the negative one of said electrodes comprising arare earth oxide.

In witness whereof I have hereunto set my hand this 26th day of March,1923.

THEODORE WILLARD CASE.

